So you’ve developed a groundbreaking product prototype that works flawlessly. The temptation is to assume that scaling up production will be a straightforward task. However, as Musk pointed out, the devil is in the details. Crafting a production process that can reliably churn out hundreds or thousands of units demands careful planning and consideration.

Selecting the correct manufacturing process at a part level can have a huge impact on the cost, quality and waste output of a product. At the prototyping stage, a variety of methods such as 3D printing and vacuum casting can be used to produce parts in low volume, to allow for proof of concept and validation of a number of features. However, these processes do not scale well, and in a lot of cases will not achieve the quality required to meet the product specifications. It is important that these considerations are made as early as possible in the design journey, as a small tweak to a component before locking in the design could save huge amounts of cost in production.

The next step is to design a simple and repeatable process for the assembly of the product. The process should be easily documented in a work instruction. Jigs and fixtures should be used to reduce the margin for error, as well as allow for multiple processes to happen in parallel. Creativity and innovation are required here as no two products will have the exact same assembly process.

When designing a process, you must also consider the quantities that are being produced. Not every assembly requires robotics or automation to make it efficient – it has to make sense relative to the output.

One of the most underrated heroes of manufacturing efficiency is jig and fixture design. These unassuming tools play a pivotal role in streamlining assembly tasks. They ensure the precise application of components, reduce human effort, and allow multiple parts to be assembled concurrently. Mastering jig and fixture design is one of the most effective ways to increase efficiency in production.For example, Jigs can be used to accurately apply gaskets, increasing leverage to reduce human effort or allow multiple parts to be assembled at the same time.

Test fixtures are also critical to ensure that tests are producing reliable results. Careful design, validation and, calibration of the test fixtures is required, as you want to ensure that you are catching defects, but not disposing of parts that are close to the upper and lower tolerance thresholds.

One of the factors that contributes to the complexity of production engineering is the requirement to consistently produce quality parts. As production scales up, so does the risk of defects. Quality control measures must be put in place to catch the defects as early in the process as possible to not only reduce waste but to minimise costs, risk of damage and maintain product integrity.

Defining Quality Requirements

Before quality checks can be put in place, it is important to define what is acceptable, and what is not. In order to do this, reference must be made to the product requirements document, risk assessment and test plan. These documents will outline what requirements need to be met, how many parts need to be checked against the requirement, and how the parts will be checked. It is also important to consider the cost of a failed unit at each stage of the manufacturing process. As the product moves through each process, and new parts are added, the cost becomes greater. To reduce the cost, parts and assemblies should be tested as early as possible.

Supplier Quality

Right at the top of the chain is the material and part supplier. Choosing the right supplier, and auditing them well is paramount to ensuring that the parts received are at an acceptable quality limit (AQL). The level of quality required will vary from part to part, so it is important to create clear documentation to communicate your quality needs with the supplier. This documentation includes drawings, Quality Checklists, Test Protocols and other documentation depending on the level of testing required, which will depend on the complexity of what the supplier is producing. They may be providing anything from a material, or a basic part, to a full electronics assembly.

In-Line Quality Checks

Even if your process is well designed, and the margin for error is reduced, there is still potential for things to go wrong in the assembly process. This can leave you with a variety of defects due to handling, incorrect assembly, and the reality that it is impossible to achieve a perfect yield. Depending on the potential severity and the recorded frequency of defects, either batch/sample checks, or 100% checks can be implemented in-line to catch defects before they move further down the line. The frequency of these checks can be determined by how serious the harm caused by a defect would be.

Functional Testing

If dysfunctional units make it out to customers it can cause a lot of damage to the brand, or worse, cause serious harm to a user. Functional tests should be performed throughout production, as soon as it is viable to do so. Some tests, such as camera calibration, require housings and lens elements to be assembled prior to testing. A quick test to test functionality at the end of the assembly process can save a lot of customer complaints and damage to your brand. It is important to note that overtesting, and under testing will both cause issues, as every test takes time and incurs cost. Through the Production Engineering process, as more units are produced, it will become evident where defects are occurring, and the impact that these defects are having. It is therefore important to have processes to collect defect data, and to use this to determine where testing should be added or removed.